Anchor assisted communication channel hopping

ABSTRACT

A method, an apparatus, and a computer program product for wireless communication are provided. In one implementation, an apparatus includes a processing system configured to attempt communication with a first device via a first channel, connect with a second device associated with the first device in response to a determination that communication with the first device was unsuccessful on the first channel, and receive channel information associated with the first device from the second device, wherein the channel information indicates a second channel used by the first device.

BACKGROUND

1. Field of the Disclosure

The present disclosure relates generally to communication systems, andmore particularly, to facilitating association between a station and achannel-hopping access point (AP).

2. Description of Related Art

In many telecommunication systems, communication networks are used toexchange messages among several interacting spatially-separated devices.Networks may be classified according to geographic scope, which couldbe, for example, a metropolitan area, a local area, or a personal area.Such networks may be designated as a wide area network (WAN),metropolitan area network (MAN), local area network (LAN), wirelesslocal area network (WLAN), or personal area network (PAN). Networks alsodiffer according to the switching/routing technique used to interconnectthe various network nodes and devices (e.g., circuit switching vs.packet switching), the type of physical media employed for transmission(e.g., wired vs. wireless), and the set of communication protocols used(e.g., Internet protocol suite, Synchronous Optical Networking (SONET),Ethernet, IEEE 802.11, etc.).

Wireless networks are often preferred when the network elements aremobile and thus have dynamic connectivity needs, or if the networkarchitecture is formed in an ad hoc, rather than fixed, topology.Wireless networks employ intangible physical media in an unguidedpropagation mode using electromagnetic waves in the radio, microwave,infra-red, optical, or other frequency bands. Wireless networksadvantageously facilitate user mobility and rapid field deployment whencompared to fixed wired networks. The various advantages provided bywireless networks lead to high levels of wireless network usage. As theusage levels of wireless networks increase, some network resources maybecome heavily loaded, thereby reducing network performance during theoverload conditions. Thus, a need exists for networking strategies andimplementations that may increase capacity and/or performance inwireless networks.

SUMMARY

The systems, methods, and devices of the present disclosure each haveseveral aspects and features. Without limiting the scope of the claimswhich follow, some features will now be discussed briefly. Afterconsidering this discussion, and particularly after reading the sectionentitled “Detailed Description,” one will understand how the features ofthe present disclosure provide advantages related to the performance ofanchor assisted communication channel hopping.

One aspect of this disclosure provides an apparatus for wirelesscommunication including a processing system configured to attemptcommunication with a first device via a first channel, connect with asecond device associated with the first device in response to adetermination that communication with the first device was unsuccessfulon the first channel, and receive channel information associated withthe first device from the second device, wherein the channel informationindicates a second channel used by the first device.

Another aspect of this disclosure provides a method of wirelesscommunication at an apparatus. The method includes attemptingcommunication with a first device via a first channel, connecting with asecond device associated with the first device in response to adetermination that communication with the first device was unsuccessfulon the first channel, and receiving channel information associated withthe first device from the second device, wherein the channel informationindicates a second channel used by the first device.

A further aspect of this disclosure provides an apparatus for wirelesscommunication including means for attempting communication with a firstdevice via a first channel, means for connecting with a second deviceassociated with the first device in response to a determination thatcommunication with the first device was unsuccessful on the firstchannel, and means for receiving channel information associated with thefirst device from the second device, wherein the channel informationindicates a second channel used by the first device.

Yet another aspect of this disclosure provides a computer-readablemedium storing computer executable code for wireless communication at anapparatus. The computer-readable medium includes code for attemptingcommunication with a first device via a first channel, connecting with asecond device associated with the first device in response to adetermination that communication with the first device was unsuccessfulon the first channel, and receiving channel information associated withthe first device from the second device, wherein the channel informationindicates a second channel used by the first device

Yet a further aspect of this disclosure provides for a station forwireless communication including at least one antenna, and a processingsystem coupled to the at least one antenna. The processing system isconfigured to attempt, via the at least one antenna, communication witha first device via a first channel, connect, via the at least oneantenna, with a second device associated with the first device inresponse to a determination that communication with the first device wasunsuccessful on the first channel, and receive, via the at least oneantenna, channel information associated with the first device from thesecond device, wherein the channel information indicates a secondchannel used by the first device.

One aspect of this disclosure provides for an apparatus for wirelesscommunication including a processing system configured to receiveinformation related to a first device, wherein the information includesan indication that the first device is configured to change itsoperating channel, exclude the first device from an available devicelist in a neighbor report in response to receiving the indication thatthe first device is configured to change its operating channel, andoutput the neighbor report for transmission to a second device.

Another aspect of this disclosure provides for a method of wirelesscommunication at an apparatus. The method includes receiving informationrelated to a first device, wherein the information includes anindication that the first device is configured to change its operatingchannel, excluding the first device from an available device list in aneighbor report in response to receiving the indication that the firstdevice is configured to change its operating channel, and outputting theneighbor report for transmission to a second device.

A further aspect of this disclosure provides for an apparatus forwireless communication including means for receiving information relatedto a first device, wherein the information includes an indication thatthe first device is configured to change its operating channel, meansfor excluding the first device from an available device list in aneighbor report in response to receiving the indication that the firstdevice is configured to change its operating channel, and means foroutputting the neighbor report for transmission to a second device.

Yet another aspect of this disclosure provides for a computer-readablemedium storing computer executable code for wireless communication at anapparatus. The computer-readable medium includes code for receivinginformation related to a first device, wherein the information includesan indication that the first device is configured to change itsoperating channel, excluding the first device from an available devicelist in a neighbor report in response to receiving the indication thatthe first device is configured to change its operating channel, andoutputting the neighbor report for transmission to a second device.

Yet a further aspect of this disclosure provides for an access point forwireless communication including at least one antenna, and a processingsystem coupled to the at least one antenna. The processing system isconfigured to receive, via the at least one antenna, information relatedto a first device, wherein the information includes an indication thatthe first device is configured to change its operating channel, exclude,via the at least one antenna, the first device from an available devicelist in a neighbor report in response to receiving the indication thatthe first device is configured to change its operating channel, andoutput, via the at least one antenna, the neighbor report fortransmission to a second device.

One aspect of this disclosure provides an apparatus for wirelesscommunication including a processing system. The processing system isconfigured to receive a request from a first device, the requestrequesting channel information regarding a second device associated withthe apparatus. The processing system is further configured to transmitthe channel information regarding the second device to the first deviceto indicate a channel used by the second device and to facilitate anattempt by the first device to communicate with the second device viathe indicated channel.

Another aspect of this disclosure provides a method of wirelesscommunication at an apparatus. The method includes receiving a requestfrom a first device, the request requesting channel informationregarding a second device associated with the apparatus. The methodfurther includes transmitting the channel information regarding thesecond device to the first device to indicate a channel used by thesecond device and to facilitate an attempt by the first device tocommunicate with the second device via the indicated channel.

A further aspect of this disclosure provides an apparatus for wirelesscommunication. The apparatus includes means for receiving a request froma first device, the request requesting channel information regarding asecond device associated with the apparatus. The apparatus furtherincludes means for transmitting the channel information regarding thesecond device to the first device to indicate a channel used by thesecond device and to facilitate an attempt by the first device tocommunicate with the second device via the indicated channel.

Yet another aspect of this disclosure provides a computer-readablemedium storing computer executable code for wireless communication at anapparatus. The computer-readable medium includes code for receiving arequest from a first device, the request requesting channel informationregarding a second device. The computer-readable medium further includescode for transmitting the channel information regarding the seconddevice to indicate a channel used by the second device and to facilitatean attempt by the first device to communicate with the second device viathe indicated channel.

Yet a further aspect of this disclosure provides for an access point forwireless communication. The access point includes at least one antennaand a processing system coupled to the at least one antenna. Theprocessing system is configured to receive, via the at least oneantenna, a request from a first device, the request requesting channelinformation regarding a second device, and transmit, via the at leastone antenna, the channel information regarding the second device to thefirst device to indicate a channel used by the second device and tofacilitate an attempt by the first device to communicate with the seconddevice via the indicated channel.

One aspect of this disclosure provides an apparatus for wirelesscommunication including a processing system. The processing system isconfigured to transmit a scanning schedule to one or more devices. Thescanning schedule includes one or more candidate channels and a scanperiod corresponding to at least a first device of the one or moredevices. The processing system is further configured to receive a reportfrom the first device in response to the scanning schedule. The reportindicates a load on at least one of the one or more candidate channelsduring the scan period.

Another aspect of this disclosure provides a method of wirelesscommunication at an apparatus. The method includes transmitting ascanning schedule to one or more devices, the scanning schedulecomprising one or more candidate channels and a scan periodcorresponding to at least a first device of the one or more devices, andreceiving a report from the first device in response to the scanningschedule. The report indicates a load on at least one of the one or morecandidate channels during the scan period.

A further aspect of this disclosure provides an apparatus for wirelesscommunication. The apparatus includes means for transmitting a scanningschedule to one or more devices, the scanning schedule comprising one ormore candidate channels and a scan period corresponding to at least afirst device of the one or more devices, and means for receiving areport from the first device in response to the scanning schedule. Thereport indicates a load on at least one of the one or more candidatechannels during the scan period.

Yet another aspect of this disclosure provides a computer-readablemedium storing computer executable code for wireless communication at anapparatus. The computer-readable medium includes code for transmitting ascanning schedule to one or more devices, the scanning schedulecomprising one or more candidate channels and a scan periodcorresponding to at least a first device of the one or more devices, andreceiving a report from the first device in response to the scanningschedule. The report indicates a load on at least one of the one or morecandidate channels during the scan period.

Yet a further aspect of this disclosure provides an access point forwireless communication. The access point includes at least one antennaand a processing system coupled to the at least one antenna. Theprocessing system is configured to transmit, via the at least oneantenna, a scanning schedule to one or more devices, the scanningschedule comprising one or more candidate channels and a scan periodcorresponding to at least a first device of the one or more devices, andreceive, via the at least one antenna, a report from the first device inresponse to the scanning schedule. The report indicates a load on atleast one of the one or more candidate channels during the scan period.

One aspect of this disclosure provides an apparatus for wirelesscommunication. The apparatus includes a processing system configured toreceive a scanning schedule from a device, the scanning schedulecomprising one or more candidate channels and a scan periodcorresponding to the apparatus, measure a load on at least one of theone or more candidate channels during the scan period in response toreceipt of the scanning schedule, and report the measured load on atleast one of the one or more candidate channels to the device.

Another aspect of this disclosure provides a method of wirelesscommunication at an apparatus. The method includes receiving a scanningschedule from a device, the scanning schedule comprising one or morecandidate channels and a scan period corresponding to the apparatus,measuring a load on at least one of the one or more candidate channelsduring the scan period in response to receipt of the scanning schedule,and reporting the measured load on at least one of the one or morecandidate channels to the device.

A further aspect of this disclosure provides an apparatus for wirelesscommunication. The apparatus includes means for receiving a scanningschedule from a device, the scanning schedule comprising one or morecandidate channels and a scan period corresponding to the apparatus,means for measuring a load on at least one of the one or more candidatechannels during the scan period in response to receipt of the scanningschedule, and means for reporting the measured load on at least one ofthe one or more candidate channels to the device.

Yet another aspect of this disclosure provides a computer-readablemedium storing computer executable code for wireless communication at anapparatus. The computer-readable medium includes code for receiving ascanning schedule from a device, the scanning schedule comprising one ormore candidate channels and a scan period corresponding to theapparatus, measuring a load on at least one of the one or more candidatechannels during the scan period in response to receipt of the scanningschedule, and reporting the measured load on at least one of the one ormore candidate channels to the device.

Yet another aspect of this disclosure provides a station for wirelesscommunication. The station includes at least one antenna and aprocessing system coupled to the at least one antenna. The processingsystem is configured to receive, via the at least one antenna, ascanning schedule from a device, the scanning schedule comprising one ormore candidate channels and a scan period corresponding to theapparatus, measure a load on at least one of the one or more candidatechannels during the scan period in response to receipt of the scanningschedule, and report, via the at least one antenna, the measured load onat least one of the one or more candidate channels to the device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an example wireless communication system in which aspectsof the present disclosure may be employed.

FIG. 2 shows a functional block diagram of an example wireless devicethat may be employed within the wireless communication system of FIG. 1.

FIG. 3A is a diagram illustrating medium usage (MU) levels for oneexample set of wireless channels.

FIG. 3B is a diagram illustrating an access point (AP) schedulingstations (STAs) to scan candidate primary channels according to a timedivision multiplexing (TDM) scheme.

FIG. 3C is a first flowchart of an example method of wirelesscommunication.

FIG. 4 is a diagram illustrating a STA attempting to scan for a hoppingAP.

FIG. 5 is a second flowchart of an example method of wirelesscommunication.

FIG. 6 is a third flowchart of an example method of wirelesscommunication.

FIG. 7 is a fourth flowchart of an example method of wirelesscommunication.

FIG. 8 is a fifth flowchart of an example method of wirelesscommunication.

FIG. 9 is a sixth flowchart of an example method of wirelesscommunication.

FIG. 10 is a seventh flowchart of an example method of wirelesscommunication.

FIG. 11 is an eighth flowchart of an example method of wirelesscommunication.

FIG. 12 is a ninth flowchart of an example method of wirelesscommunication.

DETAILED DESCRIPTION

The present disclosure describes various communication channel hoppingfeatures and implementations that may improve performance of wirelessnetworks. The channel hopping techniques disclosed herein may be used,as one example, in a wireless network that includes an access point (AP)communicating with one or more stations (STAs). During a time in whichthe AP has insufficient medium usage (MU) (e.g., due to heavy loads andcontention), there could be a lightly loaded channel that is availableand that is different than the AP's current operating channel. The APcan exploit this available bandwidth (e.g., a short-term “frequencyhole”) by quickly hopping to the lightly loaded channel by transitioningits operating channel from its previous heavily loaded channel to thenew lightly loaded channel.

However, various issues may potentially appear when the AP changes itsprimary channel. As a first example issue, a new STA may fail to findthe hopping AP on the new channel because the STA may have acquiredoutdated information from a third party that indicates the AP's use ofthe old channel. As a second example issue, a STA may fail to hop to thenew channel selected by the AP due to the STA missing a hopping schedulebroadcasted by the hopping AP. In this situation, the STA may have beenin a sleep mode during the broadcast, there may have been a decodingerror, or the STA may have been the subject of a later hand-in transfer.As a third example issue, two hopping APs may collide when they both tryto transition to the same new channel.

Each of these potential issues may be mitigated through use of an anchorAP to assist the hopping AP. In some implementations, the anchor AP mayremain on a long-term stationary primary channel. The anchor AP's use ofthe long-term stationary channel may provide a stable interface toexchange information about the hopping AP with other nodes. Thus, withthe assistance of the anchor AP, the hopping AP is free to move betweenmultiple different channels on a short-term basis with reducedlikelihood of causing the issues discussed above. For example, while thehopping AP is moving around the available channels, the hopping AP keepsthe anchor AP informed of its current channel. The anchor AP remainsavailable on a more consistent channel to provide status and locationinformation about the hopping AP to other nodes interested in theoperation of the hopping AP. Additional details regarding the hoppingAP, the anchor AP, associated STAs, and other network nodes will bediscussed in more detail below.

Various aspects of the novel systems, apparatuses, and methods aredescribed more fully hereinafter with reference to the accompanyingdrawings. This disclosure may, however, be embodied in many differentforms and should not be construed as limited to any specific structureor function presented throughout this disclosure. Rather, these aspectsare provided so that this disclosure will be thorough and complete, andwill fully convey the scope of the disclosure to those skilled in theart. Based on the teachings herein one skilled in the art shouldappreciate that the scope of the disclosure is intended to cover anyaspect of the novel systems, apparatuses, and methods disclosed herein,whether implemented independently of, or combined with, any other aspectof the disclosure. For example, an apparatus may be implemented or amethod may be practiced using any number of the aspects set forthherein. In addition, the scope of the disclosure is intended to coversuch an apparatus or method which is practiced using other structure,functionality, or structure and functionality in addition to or otherthan the various aspects of the disclosure set forth herein. It shouldbe understood that any aspect disclosed herein may be embodied by one ormore elements of a claim.

Although particular aspects are described herein, many variations andpermutations of these aspects fall within the scope of the disclosure.Although some benefits and advantages of specific aspects are mentioned,the scope of the disclosure is not intended to be limited to particularbenefits, uses, or objectives. Rather, aspects of the disclosure areintended to be broadly applicable to different wireless technologies,system configurations, networks, and transmission protocols, some ofwhich are illustrated by way of example in the figures and in thefollowing description of the disclosed aspects. The detailed descriptionand drawings are merely illustrative of the disclosure rather thanlimiting, the scope of the disclosure being defined by the appendedclaims and equivalents thereof.

The channel hopping techniques disclosed herein may be used on manydifferent types of wireless network technologies. One such network maybe a wireless local area network (WLAN). A WLAN may be used tointerconnect nearby devices together, employing networking protocols.The various aspects described herein may apply to any communicationstandard, such as a wireless protocol.

In some implementations, wireless signals in a WLAN may be transmittedaccording to an IEEE 802.11 protocol. The signals may be transmittedusing orthogonal frequency-division multiplexing (OFDM), orthogonalfrequency-division multiple access (OFDMA), direct-sequence spreadspectrum (DSSS) communications, a combination of OFDM and DSSScommunications, or other schemes. Implementations of the 802.11 protocolmay be used for sensors, metering, smart grid networks, consumerelectronics, healthcare devices, security systems, and/or processautomation. In some implementations, certain devices implementing the802.11 protocol may consume less power than devices implementing otherwireless protocols. Additionally, these 802.11 devices may be used totransmit wireless signals across a relatively long range, for example,about one kilometer or longer.

In some implementations, a WLAN includes various devices which are thecomponents that access the wireless network. For example, the networkmay include access points (“APs”) and clients (also referred to asstations, or “STAs”). In general, an AP may serve as a hub or basestation for the WLAN and a STA serves as a user of the WLAN. Forexample, a STA may be a computer, laptop computer, a tablet computer, apersonal digital assistant (PDA), a mobile phone (e.g., a “smartphone”),an Internet of Things (“IoT”) device, or another type of electroniccommunication device. In an example, a STA connects to an AP via a WiFi(e.g., IEEE 802.11 protocol) compliant wireless link to obtain generalconnectivity to the Internet or to other wide area networks. In someimplementations a STA may also be used as an AP, such a device operatingas a Software enabled Access Point (“SoftAP”).

An access point (“AP”) may also comprise, be implemented as, or known asa NodeB, Radio Network Controller (“RNC”), eNodeB, Base StationController (“BSC”), Base Transceiver Station (“BTS”), Base Station(“BS”), Transceiver Function (“TF”), Radio Router, Radio Transceiver, orsome other terminology.

A station “STA” may also comprise, be implemented as, or known as anaccess terminal (“AT”), a subscriber station, a subscriber unit, amobile station, a remote station, a remote terminal, a user terminal, auser agent, a user device, user equipment, or some other terminology. Insome implementations an access terminal may comprise a cellulartelephone, a cordless telephone, a Session Initiation Protocol (“SIP”)phone, a wireless local loop (“WLL”) station, a personal digitalassistant (“PDA”), a handheld device having wireless connectioncapability, or some other suitable processing device connected to awireless modem. Accordingly, one or more aspects taught herein may beincorporated into a phone (e.g., a cellular phone or smartphone), acomputer (e.g., a laptop), a portable communication device, a headset, aportable computing device (e.g., a personal data assistant), anentertainment device (e.g., a music or video device, or a satelliteradio), a gaming device or system, a global positioning system device,or any other suitable device that is configured to communicate via awireless medium.

As discussed above, certain devices described herein may implement the802.11 standard, for example. Such devices, whether used as a STA or APor other device, may be used for smart metering or in a smart gridnetwork. Such devices may provide sensor applications or be used in homeautomation. The devices may instead or in addition be used in ahealthcare context, for example for personal healthcare. They may alsobe used for surveillance, to enable extended-range Internet connectivity(e.g., for use with hotspots), or to implement machine-to-machinecommunications.

FIG. 1 shows an example wireless communication system 100 in whichaspects of the present disclosure may be employed. The wirelesscommunication system 100 may operate pursuant to a wireless standard,for example the 802.11 standard. The wireless communication system 100may include an AP 104, which communicates with STAs 106 (e.g., includingSTA 106 a, STA 106 b, STA 106 c, and STA 106 d, as shown in FIG. 1).

A variety of processes and methods may be used for transmissions in thewireless communication system 100 between the AP 104 and the STAs 106.For example, signals may be sent and received between the AP 104 and theSTAs 106 in accordance with OFDM/OFDMA techniques. If this is the case,the wireless communication system 100 may be referred to as anOFDM/OFDMA system. Alternatively, signals may be sent and receivedbetween the AP 104 and the STAs 106 in accordance with Code DivisionMultiple Access (CDMA) techniques. If this is the case, the wirelesscommunication system 100 may be referred to as a CDMA system.

A communication link that facilitates transmission from the AP 104 toone or more of the STAs 106 may be referred to as a downlink (DL) 108,and a communication link that facilitates transmission from one or moreof the STAs 106 to the AP 104 may be referred to as an uplink (UL) 110.Alternatively, a downlink 108 may be referred to as a forward link or aforward channel, and an uplink 110 may be referred to as a reverse linkor a reverse channel. DL communications may include unicast or multicasttraffic indications.

The AP 104 may suppress adjacent channel interference (ACI) so that theAP 104 may receive UL communications on more than one channelsimultaneously without causing significant analog-to-digital conversion(ADC) clipping noise. The AP 104 may improve suppression of ACI, forexample, by having separate finite impulse response (FIR) filters foreach channel or having a longer ADC backoff period with increased bitwidths.

The AP 104 may act as a base station and provide wireless communicationcoverage in a basic service area (BSA) 102. The AP 104 along with theSTAs 106 associated with the AP 104 and that use the AP 104 forcommunication may be referred to as a basic service set (BSS). It shouldbe noted that the wireless communication system 100 may not have acentral AP (e.g., the AP 104), but rather may function as a peer-to-peernetwork between the STAs 106. Accordingly, the functions of the AP 104described herein may alternatively be performed by one or more of theSTAs 106.

The AP 104 may transmit a beacon signal (or simply a “beacon”) on one ormore channels (e.g., multiple channels, each channel including afrequency bandwidth), via a communication link such as the downlink 108,to other nodes (e.g., the STAs 106 of the wireless communication system100). The beacon signal may help the other nodes to synchronize theirtiming with the AP 104, or may provide other information orfunctionality. Such beacons may be transmitted periodically. The periodbetween successive transmissions may be referred to as a superframe.Transmission of a beacon may be divided into a number of groups orintervals. The beacon may include, but is not limited to, suchinformation as timestamp information to set a common clock, apeer-to-peer network identifier, a device identifier, capabilityinformation, a superframe duration, transmission direction information,reception direction information, a neighbor list (or neighbor report),and/or an extended neighbor list, some of which are described inadditional detail below. Thus, a beacon may include information bothcommon (e.g., shared) amongst several devices, and information specificto a given device.

In some implementations, a STA 106 may be required to associate with theAP 104 in order to send communications to and/or receive communicationsfrom the AP 104. Information for associating may be included in a beaconbroadcast by the AP 104. To receive such a beacon, the STA 106 may, forexample, perform a broad coverage search over a coverage region. Asearch may also be performed by the STA 106 by sweeping a coverageregion in a lighthouse fashion, for example. After receiving theinformation for associating, the STA 106 may transmit a referencesignal, such as an association probe or request, to the AP 104. In someimplementations, the AP 104 may use backhaul services, for example, tocommunicate with a larger network, such as the Internet or a publicswitched telephone network (PSTN).

FIG. 2 shows an example functional block diagram of a wireless device202 that may be employed within the wireless communication system 100 ofFIG. 1. The wireless device 202 is an example of a device that may beconfigured to implement the various methods described herein. Forexample, the wireless device 202 may serve as the AP 104 or as one ofthe STAs 106 in the context of the system of FIG. 1. Specifically, thewireless device 202 may be a “hopping” AP, an “anchor” AP, or a STAcommunicating with the hopping AP and/or the anchor AP, as discussedherein.

The wireless device 202 may include a processor 204 which controlsoperation of the wireless device 202. The processor 204 may also bereferred to as a central processing unit (CPU). Memory 206, which mayinclude both read-only memory (ROM) and random access memory (RAM), mayprovide instructions and data to the processor 204. A portion of thememory 206 may also include non-volatile random access memory (NVRAM).The processor 204 typically performs logical and arithmetic operationsbased on program instructions stored within the memory 206. Theinstructions in the memory 206 may be executable by the processor 204 toimplement the anchor assisted channel hopping methods described herein.

The processor 204 may comprise, or be a component of, a processingsystem implemented with one or more processors. The one or moreprocessors may be implemented with any combination of general-purposemicroprocessors, microcontrollers, digital signal processors (DSPs),field programmable gate array (FPGAs), programmable logic devices(PLDs), controllers, state machines, gated logic, discrete hardwarecomponents, dedicated hardware finite state machines, or any othersuitable entities that can perform calculations or other manipulationsof information. In one implementation, the processor 204 may be aspecialized processor with an architecture customized for theoperational needs of an AP providing WLAN services or a STAcommunicating over a WLAN.

The processing system may also include machine-readable media forstoring software. Software shall be construed broadly to mean any typeof instructions, whether referred to as software, firmware, middleware,microcode, hardware description language, or otherwise. Instructions mayinclude code (e.g., in source code format, binary code format,executable code format, or any other suitable format of code). Theinstructions, when executed by the one or more processors, cause theprocessing system to perform the various functions described herein. Forexample, the instructions stored on the memory 206 may includeinstructions programmed specifically for the particular anchor assistedchannel hopping functions described herein.

The wireless device 202 may also include a housing 208 that may includea transmitter 210 and/or a receiver 212 to allow transmission andreception of data between the wireless device 202 and a remote location.The transmitter 210 and receiver 212 may be combined into a transceiver214. An antenna 216 may be attached to the housing 208 and electricallycoupled to the transceiver 214. The wireless device 202 may also includemultiple transmitters, multiple receivers, multiple transceivers, and/ormultiple antennas.

The wireless device 202 may also include a signal detector 218 that maybe used in an effort to detect and quantify the level of signalsreceived by the transceiver 214. The signal detector 218 may detect suchsignals as total energy, energy per subcarrier per symbol, powerspectral density and other signals. The wireless device 202 may alsoinclude a digital signal processor (DSP) 220 for use in processingsignals. The DSP 220 may be configured to generate a packet fortransmission. The packet may comprise a physical layer data unit (PPDU).

The wireless device 202 may further comprise a user interface 222 insome implementations. The user interface 222 may comprise a keypad, amicrophone, a speaker, and/or a display. The user interface 222 mayinclude any element or component that conveys information to a user ofthe wireless device 202 and/or receives input from the user.

The various components of the wireless device 202 may be coupledtogether by a bus system 226. The bus system 226 may include a data bus,for example, as well as a power bus, a control signal bus, and a statussignal bus in addition to the data bus. Components of the wirelessdevice 202 may be coupled together or accept or provide inputs to eachother using some other mechanism.

Although a number of separate components are illustrated in FIG. 2, oneor more of the components may be combined or commonly implemented. Forexample, the processor 204 may be used to implement not only thefunctionality described above with respect to the processor 204, butalso to implement the functionality described above with respect to thesignal detector 218 and/or the DSP 220. Further, each of the componentsillustrated in FIG. 2 may be implemented using a plurality of separateelements.

The wireless device 202 may comprise an AP 104 or a STA 106, and may beused to transmit and/or receive various communications including pollingmessages, beacon signals, or paging messages, for example. That is,either AP 104 or STA 106 may serve as transmitter or receiver of pollingmessages, beacon signals, or paging messages. The signal detector 218may be used by software running on memory 206 and processor 204 todetect the presence of a transmitter or receiver. The AP 104 and STA 106may receive or transmit messages on one or more channels forcommunication.

The STA 106 (FIG. 1) may have a plurality of operational modes. Forexample, the STA 106 may have a first operational mode referred to as anactive mode. In the active mode, the STA 106 may be in an “awake” stateand actively transmit/receive data with the AP 104. Further, the STA 106may have a second operational mode referred to as a power save mode. Inthe power save mode, the STA 106 may be in the “awake” state or a “doze”or “sleep” state where the STA 106 does not actively transmit/receivedata with the AP 104. For example, the receiver 212, DSP 220, and/orsignal detector 218 of the STA 106 may operate using reduced powerconsumption in the power save mode. Further, in the power save mode, theSTA 106 may occasionally enter the awake state to listen to messagesfrom the AP 104 (e.g., paging messages configured to indicate towireless devices whether or not the wireless devices have trafficpending and buffered at another device) that indicate to the STA 106whether or not the STA 106 needs to “wake up” (e.g., enter the awakestate) at a certain time so as to be able to transmit/receive data withthe AP 104.

FIG. 3A is a diagram 300 illustrating medium usage (MU) levels for oneexample set of wireless channels. In some implementations, when an AP'soperating channel experiences high load, the AP may insufficiently useits resource medium (insufficient MU). However, other channels outsideof the AP's operating channel may exist that experience low load, andwhich the AP may use. For example, referring to FIG. 3A, the AP mayoperate on a first 80 MHz channel 302 (80 MHz Ch1). While using channel302, the AP may experience insufficient MU due to high contention withnodes of an overlapping basic service set (OBSS). Accordingly, the APmay look to one of the five other 80 MHz channels of an entire WiFibandwidth to assess whether one of the other channels currentlyexperiences, and/or will continue to experience (e.g., for apredetermined time period, such as for the next ten minutes), a lightload. The AP may then change its current operating channel (e.g.,channel 302, 80 MHZ Ch1) by hopping to a lightly loaded channel toexploit the short-term “frequency hole” (lightly loaded channel). Asshown in FIG. 3A, the fourth 80 MHz channel 304 (80 MHz Ch4) has beenidentified as having a light load. Accordingly, the AP may hop tochannel 304, and operate on channel 304 for as long as the channelexperiences the light load. Although FIG. 3A illustrates one exampleusing 80 MHz channels, the anchor assisted channel hopping techniquesdisclosed herein may also be used in other size channels, such as 20 MHzchannels, 40 MHz channels, 160 MHz channels, etc. Furthermore, in someimplementations, the anchor assisted channel hopping techniquesdisclosed herein may also be used within sub-portions (e.g., toneblocks) of a full channel.

Previous channel allocation techniques may not be able to change anoperating channel quickly to exploit short-term frequency holes outsideof an AP's current operating channel. In one example allocationtechnique, such as long-term primary channel selection, the AP'sselected primary channel may not change for a long period of time. Forexample, the selected primary channel may not change for at leastseveral hours, or may even remain fixed after AP setup. The relativelyfixed nature of the selected channel with this technique helps mobilityin that one AP can better track and identify the primary channel ofneighbor APs in a neighbor report. STAs use the neighbor report toquickly find neighbor APs for handover. However, using the long-termprimary channel selection technique may not help with exploiting theshort-term “frequency hole” situation where alternative channels mayprovide a lower load level since the primary channel cannot be changedfrequently (e.g., may not be able to change every few minutes).

In another example allocation technique, such as a physical layer dataunit (PPDU) frequency division multiplexing (FDM) transmissionopportunity (TXOP) hopping technique, if the AP on the primary channeldetects an OBSS PPDU not using an entire bandwidth of another AP'soperating channel, the AP may transmit on a portion of the bandwidth notused by the PPDU in the duration of the PPDU. However, it may bedifficult for the AP to hop outside of a current operating channel toexploit out-of-band frequency holes since doing so may require changingan analog filter, which may not be done quickly (e.g., within theduration of the OBSS PPDU).

In some implementations, the present disclosure improves upon theprevious hopping techniques by providing an AP (“hopping AP”) that isable to change primary channels on a short-term basis (e.g., every fewminutes) to exploit frequency holes of an entire bandwidth. Theseimplementations mitigate issues related to primary channel hopping byusing an anchor AP having a long-term stationary primary channel, whichprovides a stable interface for exchanging information about the hoppingAP with other nodes. The anchor AP may be co-located with the hoppingAP. As one example, the hopping AP and the anchor AP may be physicallylocated within the same AP housing structure, such as within the housing208 of FIG. 2. As another example, the hopping AP and the anchor AP maybe physically separated in different devices but are positioned andconfigured to have an overlapping service area.

In one implementation, if two co-located APs are provided, one AP may bea hopping AP operating on a first channel, and the other AP may be ananchor AP operating on a second channel that is different than the firstchannel. The second channel may be in a different bandwidth than thesecond channel. For example, the first channel may be a channel in the 5GHz spectrum and the second channel may be a channel in the 2.4 GHzspectrum. Alternative examples may use two different channels selectedfrom other spectrum ranges, such as any of the 900 MHz, 2.4 GHz, 3.6GHz, 4.9 GHz, 5 GHz, 5.9 GHz, and 60 GHz frequency bands. Other examplesmay use spectrum ranges outside of traditional WLAN frequency bands. Thehopping AP may be able to perform short-term primary channel hopping,e.g., after a predetermined minimum interval (e.g., one minute, twominutes, three minutes, five minutes, or some other predeterminedthreshold). The hopping AP may hop to a primary channel across an entireWiFi bandwidth or even to a non-WiFi bandwidth. The minimum interval maybe short enough to exploit short-term frequency holes but also longenough to reduce time overhead due to channel hopping and scanning. Forexample, the minimum interval may be selected so that the time overheadmay be kept to less than 1%, 2%, 3%, 5%, or some other predeterminedoverhead threshold.

As stated above, the anchor AP with the long-term stationary primarychannel may help resolve issues related to changing the primary channelof the hopping AP during operation. For example, when the hopping APperforms primary channel hopping, new STAs receiving an OBSS AP'sneighbor report (NR) may fail to find the hopping AP if the NR includesoutdated primary channel information for the hopping AP. Accordingly, aSTA may be redirected to the hopping AP on the hopping AP's new channelvia an anchor AP's up-to-date neighbor report. Alternatively, an OBSS APmay exclude the hopping AP from the OBSS AP's neighbor report such thatthe STA will not know to search for the hopping AP upon receiving theOBSS AP's neighbor report. Instead, the OBSS AP's neighbor report willguide the STA to the anchor AP. The STA may then learn of the identityof the hopping AP via an indication from the anchor AP.

In another example, as the hopping AP performs primary channel hopping,a STA may fail to hop to a new primary channel due to being unaware ofthe hopping AP's hopping schedule. For example, the STA may fail toreceive the hopping schedule broadcasted by the hopping AP due to theSTA being in an extended sleep state, a decoding error, or later hand-in(e.g., STA switches to the old primary channel of the hopping AP toolate to receive the hopping schedule). Accordingly, in these situations,the STA may fall back to the anchor AP to retrieve the hopping AP's newprimary channel information. Alternatively, the hopping schedule may beindicated in an association/probe response message from the hopping AP,as well as from the anchor AP.

In some situations, two or more hopping APs may collide due to theselection of the same new primary channel on which to hop. To mitigatethe chance of one AP selecting the same hopping channel at the same timeas neighbor hopping APs, a hopping AP may monitor the hopping scheduleof the neighbor hopping APs and avoid selecting a primary channel at atime when one or more of the neighbor hopping APs select the sameprimary channel. Alternatively, the hopping AP may inform the neighborhopping APs of its hopping schedule. Thus, the neighbor hopping APs mayavoid selecting a primary channel at a time when the hopping AP selectsthe same primary channel. In a further alternative implementation, thehopping AP may disable channel hopping on a short-term basis whendetecting the existence of one or more neighbor hopping APs that arealso channel hopping on the short-term basis. As described above, thehopping AP monitoring the hopping schedule of the neighbor hopping APs,informing the neighbor hopping APs of its hopping schedule, anddetecting the existence of the neighbor hopping APs may all be performedwith the assistance of an anchor AP. For example, because the anchor APprovides a stable interface for exchanging information about a hoppingAP with other nodes, the anchor AP may assist the hopping AP withmonitoring the hopping schedule of the neighbor hopping APs byascertaining the hopping schedules of each of the neighbor hopping APsand providing the schedules to the hopping AP (e.g., via a neighborreport). In another example, the anchor AP may assist the hopping APwith informing the neighbor hopping APs of its hopping schedule byreceiving the hopping AP's hopping schedule and providing the hoppingschedule to the neighbor hopping APs (e.g., via a neighbor report). In afurther example, the anchor AP may assist the hopping AP with detectingthe existence of a neighbor hopping APs by ascertaining whether one ormore neighbor hopping APs is capable of channel hopping on a short-termbasis and informing the hopping the AP of the existence of the one ormore neighbor hopping APs that channel hop on the short-term basis.

One example scanning and hopping operation of a hopping AP will now bedescribed. A hopping AP may initiate scanning for a new primary channelacross an entire WiFi bandwidth. For example, the scanning may beinitiated if a total load on a current primary channel is greater than apredetermined threshold (e.g., 50%, 60%, 70%, 80%, 90%, etc.) and atotal medium usage (MU) of the hopping AP's own BSS nodes (e.g., STAs)is less than a predetermined threshold (e.g., 50%, 40%, 30%, 20%, 10%,etc.). The hopping AP may compare the measured loads to the respectivepredetermined thresholds, and determine whether to initiate a scan basedon the results of the threshold comparisons. The hopping AP may schedulescanning according to the following options.

In a first option, the AP schedules scanning during a common scanningperiod in which all nodes in the BSS tune to candidate new primarychannels to measure load. The scanning schedule may be sent via beacons,probe/association responses, action frames, etc. The scanning schedulemay also include a list of the candidate primary channels. The AP mayalso schedule peer-to-peer (P2P) transmissions during the scanningperiod to save resources.

In a second option, the AP schedules STAs to scan candidate primarychannels according to a time division multiplexing (TDM) scheme. FIG. 3Bis a diagram 350 illustrating the AP scheduling the STAs according tothe TDM scheme. Referring to FIG. 3B, the AP may transmit a TDM scanningschedule 352 to all STAs in the BSS. The TDM scanning schedule 352 mayinclude scan periods corresponding to different time periods, anassignment of STAs to particular scan periods, and a list of candidateprimary channels for the STAs to scan. A STA assigned to a particularscan period performs scanning during the assigned scan period. While theassigned STA performs scanning during the scan period, other STAs notassigned to the scan period (e.g., non-scanning STAs) are served by theAP. In an example of the second option, the AP may transmit a TDMscanning schedule 352 to three STAs: STA0, STA1, and STA2. STA0 may beassigned to a first scan period 354, STA1 may be assigned to a secondscan period 356, and STA2 may be assigned to a third scan period 358.Accordingly, while STA0 performs scanning of candidate primary channelsduring the first scan period 354 corresponding to a first time period,the AP may communicate data 360 with STA1 and STA2 during the first timeperiod. Similarly, while STA1 performs scanning of candidate primarychannels during the second scan period 356 corresponding to a secondtime period, the AP may communicate data 362 with STA0 and STA2 duringthe second time period. And while STA2 performs scanning of candidateprimary channels during the third scan period 358 corresponding to athird time period, the AP may communicate data 364 with STA0 and STA1during the third time period. Uplink traffic may be scheduled duringtime intervals outside of downlink traffic time intervals.

In a third option, an AP (or STA) scans candidate primary channels witha dedicated scanning hardware device. Use of a dedicated scanning deviceallows the AP and STA to focus on data communication while the dedicatedscanning device performs the load scans. The dedicated scanning devicemay be co-located together with an AP or a STA, or may be a physicallyseparated device that has a scanning range that overlaps with theservice area of the AP.

Based on a load report from all measuring nodes, the hopping APdetermines whether a candidate primary channel is “qualified” to be theAP's new operating channel based on the available medium usage (MU) onthe candidate primary channel and a current total MU of the hopping AP'sown BSS nodes. For example, in one implementation, the candidate channelmay be identified as “qualified” when the available medium usage (MU) onthe candidate primary channel is greater than a predetermined threshold(e.g., X times, wherein X may be a value of 2) above a current total MUof the hopping AP's own BSS nodes. For a candidate primary channel:

1) Available MU per measuring node=1−(load measured on the candidateprimary channel); and

2) Available MU=minimum of Available MU per measuring node, across allmeasuring nodes.

If multiple “qualified” primary channels exist, the hopping AP mayselect the primary channel with the highest Available MU. The hopping APmay send out a hopping schedule if a time since a last hop is greaterthan a predetermined minimum hopping interval threshold (e.g., threeminutes, etc.). The hopping schedule may include a target time to hop,the new primary channel, and a bandwidth.

FIG. 3C is a flowchart of an example method 370 of wirelesscommunication. The method 370 may be performed using an apparatus (e.g.,the wireless device 202 of FIG. 2). For example, the functions describedin connection with FIG. 3C may be programmed as particularcomputer-readable instructions in memory 206. The wireless device 202may then achieve the described functions when the processor 204 executesthe stored instructions programmed into the memory 206. Although themethod 370 is described below with respect to the elements of wirelessdevice 202 of FIG. 2, other components may be used to implement one ormore of the steps described herein. The apparatus performing the method370 may be a hopping-capable AP capable of channel hopping on ashort-term basis.

At block 375, the apparatus determines a first load (e.g., total load)on an operating channel (e.g., current primary channel). At block 380,the apparatus determines a second load on the operating channel causedby at least one node of a basic service set (BSS) associated with theapparatus. For example, the apparatus may determine the second load bydetermining a medium usage (MU) on the current primary channel withrespect to nodes (e.g., STAs) within the apparatus' own BSS.

At block 385, the apparatus facilitates the at least one node toinitiate scanning of one or more candidate operating channels when thefirst load is greater than a first predetermined threshold (e.g.,greater than 80% or another level) and the second load is less than asecond predetermined threshold (e.g., less than 20% or another level).In some implementations, the apparatus may facilitate the at least onenode to initiate the scanning by scheduling nodes of the BSS to measurea load on the one or more candidate operating channels during a commonscanning period. Thereafter, the apparatus may transmit informationincluding the scheduling to the at least one node. In someimplementations, the apparatus may facilitate the at least one node toinitiate the scanning by assigning nodes of the BSS to measure a load onthe one or more candidate operating channels, and scheduling each of theassigned nodes to measure the load on the one or more candidateoperating channels during a corresponding scanning period. Thereafter,the apparatus may transmit, to the at least one node, informationincluding an identification of the assigned nodes and the scheduling.The information may also include an identification of the one or morecandidate operating channels on which to measure the load.

At block 390, the apparatus selects one of the one or more candidateoperating channels as a new operating channel based on a scanning reportfrom the at least one node.

Aspects related to a hopping AP channel hopping on a short-term basisand an anchor AP providing assistance to resolve issues associated withthe short-term hopping are described below. The hopping AP and theanchor AP may be co-located APs (e.g., have at least partiallyoverlapping coverage areas), wherein the hopping AP channel hops at ahigher rate than the anchor AP (e.g., the hopping AP changes channels onaverage over a monitored time period more frequently than the anchorAP).

FIG. 4 is a diagram 400 illustrating a STA attempting to scan for ahopping AP. In FIG. 4, a hopping AP 404 of a basic service area (BSA)402 may hop to a new primary channel. Overlapping basic service set(OBSS) STAs associated with an OBSS AP 408 may eventually detect the newprimary channel of the hopping AP 404. However, the OBSS STAs may not beable to report the new primary channel to the OBSS AP 408 prior to theOBSS AP 408 transmitting an OBSS neighbor report 412. The OBSS neighborreport 412 may be sent via a beacon or a probe/association responsemessage, for example. Accordingly, the OBSS neighbor report 412 will notidentify the new primary channel of the hopping AP 404. A new scanningSTA 406 receiving the OBSS neighbor report 412 will perform a scan 410for the hopping AP 404 based on the OBSS neighbor report 412. However,the STA 406 will fail to find the hopping AP 404 since it will havereceived outdated primary channel information with respect to thehopping AP 404 in the OBSS neighbor report 412. This may trigger thescanning STA 406 to perform a costly full scan for the hopping AP 404.

Aspects of the present disclosure are provided to prevent the STA 406from performing a full scan for the hopping AP 404. The STA 406 may beredirected to the hopping AP 404 via an anchor AP's up-to-date neighborreport. Referring to FIG. 4, an anchor AP 420 is co-located with thehopping AP 404 in the BSA 402 and may operate on a long-term stationaryprimary channel. In some implementations, the anchor AP 420 provides acoverage area no less than the hopping AP 404 so that the anchor AP 420may provide assistance information to the STA 406 in the coverage areaof the hopping AP 404. For example, the anchor AP 420 may provide acoverage area that is larger than the coverage area of the hopping AP404. The anchor AP 420 may operate on the 2.4 GHz bandwidth while thehopping AP 404 may operate on the 5 GHz bandwidth, although use ofalternative bandwidths is also available in other implementations. Thescanning STA 406 may reliably find the anchor AP 420 based on the OBSSneighbor report 412 from the OBSS AP 408. For example, the anchor AP 420may be identified in the OBSS neighbor report 412. Once the STA 406locates the anchor AP 420, the STA 406 may receive a neighbor report 422from the anchor AP 420. The neighbor report 422 may include currentprimary channel information of the hopping AP 404. Accordingly, the STA406 may locate the hopping AP 404 based on the current information, thusavoiding the performance of a full scan.

To prevent the STA 406 from performing a full scan for the hopping AP404, the OBSS AP 408 may exclude identification of the hopping AP 404 inthe OBSS neighbor report 412. The hopping AP 404 may include a hoppingAP indicator in a beacon and/or probe/association response message. Theanchor AP 420 may also indicate the hopping AP 404 as a hopping AP byidentifying the hopping AP 404 in a beacon and/or probe/associationresponse message. OBSS STAs associated with the OBSS AP 408 will detecteither of the indications and inform the OBSS AP 408 accordingly.Additionally or alternatively, the OBSS AP 408 may directly detect thatthe AP 404 is a hopping AP. Upon detecting that the hopping AP 404 is ahopping AP, the OBSS AP 408 will not identify the hopping AP 404 in theOBSS neighbor report 412. Accordingly, the STA 406 is prevented fromsearching for the hopping AP 404 when performing a scan based on thereceived OBSS neighbor report 412 since the hopping AP 404 will notappear as an available neighbor AP in the report.

Aspects related to a STA associated with a hopping AP and the STA losingtrack of a hopping primary channel (e.g., failing to hop to a newprimary channel) are described below. A STA may fail to receive ahopping schedule broadcasted by the hopping AP due to the STA being inan extended sleep state, a decoding error, or later hand-in. This maytrigger the STA to perform a costly full scan to find the hopping AP.The problem may be pronounced if the hopping AP channel hops on ashort-term basis.

When the STA fails to receive the hopping AP's hopping schedule, the STAmay fall back to an anchor AP to retrieve the hopping AP's currentprimary channel information. Mapping between the anchor AP and thehopping AP may first be signaled to the STA. For example, the hopping APmay indicate a corresponding anchor AP identification and primarychannel number in a beacon and/or probe/association response message tothe STA. Similarly, the anchor AP may indicate a corresponding hoppingAP identification in a beacon and/or probe/association response messageto the STA.

Once the STA is aware of the mapping between the anchor AP and thehopping AP, the STA will wait to receive the hopping AP's beacon. If theSTA does not detect the hopping AP's beacon for a number of cycles, theSTA will communicate with the corresponding anchor AP to receive anup-to-date neighbor report. If the hopping AP's primary channel haschanged as indicated in the anchor AP's neighbor report, the STA willsearch for the hopping AP on the new primary channel. However, if thehopping AP's primary channel has not changed as indicated in the anchorAP's neighbor report, then the STA is likely beyond the coverage area ofthe hopping AP, and the STA should search for another AP with which toassociate.

The hopping AP's hopping schedule may also be indicated in the hoppingAP's association/probe response message to the STA. The hopping AP'shopping schedule may also be indicated in the anchor AP's beacon and/orassociation/response message to the STA. The hopping schedule mayinclude a target time to hop, an identification of the new primarychannel, and a bandwidth. Accordingly, STAs newly associated with thehopping AP can determine in which frames the hopping AP will hop, evenwhen failing to receive the hopping schedule previously broadcasted bythe hopping AP.

In some implementations, a STA (e.g., legacy STA) may not be able tounderstand the indicated correspondence between the anchor AP and thehopping AP or the indication of the hopping AP's hopping schedule, asdescribed above. Hence, such a STA is not able to fall back to theanchor AP if the STA loses track of the hopping AP's primary channel.Accordingly, aspects of the present disclosure for resolving such issueare described below.

In this situation, the hopping AP may send a neighbor report to the STA,wherein the only AP identified in the neighbor report is the anchor APcorresponding to the hopping AP. Based on the neighbor report, the STAmay search for the anchor AP to retrieve information related to thehopping AP when the STA loses track of the hopping AP's primary channel.

In some implementations, the STA may be prevented from associating withthe hopping AP. For example, the hopping AP may only allow a STA that iscapable of short-term channel hopping to associate with the hopping AP.The STA may be “capable” of short-term channel hopping to associate withthe hopping AP if the STA is able to recognize the anchor AP associatedwith the hopping AP and retrieve the hopping AP's hopping schedule fromthe anchor AP when the STA loses track of the hopping AP's movement. ASTA that is capable of short-term channel hopping may send a “hoppingcapable STA” indicator in a probe/association request message to thehopping AP. The hopping AP may then send a probe/association responsemessage only to the STAs that provided an indication of being “hoppingcapable.” As such, the STA that is not capable of short-term channelhopping will not receive the probe/association response message from thehopping AP, and will therefore not be able to associate with the hoppingAP.

The anchor AP and/or an OBSS AP may not advertise the hopping AP to aSTA not capable of short-term channel hopping. For example, the hoppingAP may be excluded from a neighbor AP report element sent to the STA.Alternatively, the anchor AP and/or the OBSS AP may advertise thehopping AP's primary channel information in a different message, such asa “neighbor hopping AP report” element, which cannot be understood bythe STA not capable of short-term channel hopping.

In some implementations, the hopping AP may disable channel hopping whenserving a STA not capable of short-term channel hopping. For example,after associating with one or more STAs not capable of short-termchannel hopping, the hopping AP may disable short-term primary channelhopping. The hopping AP then becomes a “regular” AP, and may ceasetransmission of a “hopping capable” indicator. Moreover, the anchor APand/or the OBSS AP may advertise the hopping AP as a regular AP in aneighbor report.

A separate AP may be provided to serve one or more STAs not capable ofshort-term channel hopping. For example, two co-located APs may bedeployed to operate on a 5 GHz channel, wherein one AP is a hopping APand the other AP is a regular AP. A STA not capable of short-termchannel hopping may be served by the regular AP, while a STA capable ofshort-term channel hopping may be served by the hopping AP. In addition,a third co-located anchor AP operating on a 2.4 GHz channel may bedeployed along with the two co-located APs operating on the 5 GHzchannel.

Aspects related to a collision of multiple hopping APs are describedbelow. In some situations, multiple hopping APs may select the same newprimary channel on which to hop during a similar time period. This mayoccur when two or more hopping APs detect the same most lightly loadedprimary channel at the same time and a hopping schedule sent by ahopping AP on a primary channel is not detected by one or more neighborhopping APs on a different primary channel. No collision may occur ifthe hopping schedule is detected by the one or more neighbor hoppingAPs. A neighbor hopping AP may also send its own hopping schedule on itsown primary channel. Collision may occur when both hopping APs selectthe same new primary channel as either of the APs may remain on the newprimary channel for a minimum interval.

Aspects related to preventing the collision of multiple hopping APs willnow be described. A hopping AP may monitor a hopping schedule ofneighbor hopping APs. The hopping schedule of a neighbor hopping AP maybe sent by an anchor AP corresponding to the neighbor hopping AP. Theneighbor hopping AP's hopping schedule may be sent on a fixed primarychannel of the corresponding anchor AP via a beacon and/orprobe/association response message. Alternatively, the neighbor hoppingAP's hopping schedule may be sent on a commonly agreed discovery channelduring a commonly agreed time interval.

The hopping AP (or corresponding anchor AP) and its associated STAs mayalso monitor a hopping schedule of a neighbor hopping AP sent by an OBSSAP. For example, the hopping schedule may be monitored by periodicallymonitoring a beacon sent by an OBSS anchor AP. Alternatively, theneighbor hopping AP's hopping schedule may be monitored by monitoringschedules sent on the commonly agreed discovery channel.

If the hopping AP detects that the neighbor hopping AP has scheduled tohop to a new primary channel at a time X for a minimum dwelling intervalY, then the hopping AP may consider not hopping to the new primarychannel before a certain time (e.g., time X+interval Y).

In some implementations, the neighbor hopping AP may be informed of thehopping AP's hopping schedule. For example, the hopping AP's hoppingschedule may be sent to each neighbor anchor AP. A sender of the hoppingschedule may be the hopping AP generating the schedule, an anchor APcorresponding to the hopping AP, or any STA associated with the hoppingAP or the anchor AP. The sender may tune to the neighbor anchor AP'slong-term stationary primary channel and send the hopping schedule onthe long-term stationary primary channel accordingly. Based on thereceived hopping schedule, the neighbor anchor AP will inform acorresponding neighbor hopping AP not to hop to the same primary channelbefore a certain time.

In other implementations, a hopping-capable AP may disable hopping if aneighbor hopping AP exists. For example, after hopping is enabled at theneighbor hopping AP, the neighbor hopping AP will transmit a “hoppingAP” indicator while a corresponding neighbor anchor AP will transmit an“anchor AP” indicator. An indicator may be sent in a beacon, and/orprobe/association response message. When the hopping-capable AP (capableof short-term channel hopping) detects that no neighbor AP transmits the“hopping AP” indicator, and therefore no threat of collision exists, thehopping-capable AP will enable hopping. Otherwise, when thehopping-capable AP detects that the neighbor AP transmits the “hoppingAP” indicator, a threat of collision exists, and the hopping-capable APwill disable hopping. The detection may be performed by monitoringbeacons of neighbor APs (e.g., neighbor anchor APs) at setup and/orperiodically (e.g., once per hour). Moreover, the detection may beperformed by the hopping-capable AP itself, an anchor AP correspondingto the hopping-capable AP, and/or one or more STAs associated with thehopping-capable AP or the anchor AP.

As described above, the existence of a hopping AP may cause neighborhopping-capable APs to disable hopping. Accordingly, aspects related toimproving fairness among hopping-capable APs (e.g., facilitatinghopping-capable APs to alternate at enabling hopping) will now bedescribed. In one example, each AP may enable hopping only for a maximumduration (e.g., one hour) and disable hopping during a following timeinterval for a minimum duration (e.g., 5 minutes). Thereafter, a firstAP may re-enable hopping if the first AP does not detect a “hopping AP”indicator from any other AP. During the time interval in which the firstAP disables hopping, a second neighbor AP may enable hopping if thesecond neighbor AP does not detect a “hopping AP” indicator from thefirst AP or any other AP. A time interval in which any AP disableshopping may be signaled to other STAs/APs by a corresponding anchor AP.This allows another AP to enable hopping during a time interval in whichall neighbor APs disable hopping.

In another example, hopping-capable APs may enable hopping based onrandom contention in synchronized time slots. This may be facilitated byAP coordination. A timeframe may be divided into multiple slots having aduration (e.g., one hour). At the beginning of a slot, eachhopping-capable AP may select a random time during a time interval(e.g., five minutes). At the selected time, a hopping-capable AP willenable hopping if the hopping-capable AP does not detect a “hopping AP”indicator from any neighbor AP.

FIG. 5 is a flowchart of an example method 500 of wirelesscommunication. The method 500 may be performed using an apparatus (e.g.,the wireless device 202 of FIG. 2, anchor AP 420, or OBSS AP 408). Forexample, the functions described in connection with FIG. 5 may beprogrammed as particular computer-readable instructions in memory 206.The wireless device 202 may then achieve the described functions whenthe processor 204 executes the stored instructions programmed into thememory 206. Although the method 500 is described below with respect tothe elements of wireless device 202 of FIG. 2, other components may beused to implement one or more of the steps described herein.

The apparatus may be configured to communicate with a station (e.g., STA106 or STA 406) regarding association between the station and a device(e.g., hopping AP). The apparatus and the device may have overlappingcoverage areas and the device may channel hop on a short-term basis(e.g., at a higher rate than the apparatus).

At block 505, the apparatus receives information related to a firstdevice, wherein the information includes an indication that the firstdevice is configured to change its operating channel. At block 510, theapparatus excludes the first device from an available device list in aneighbor report in response to receiving the indication that the firstdevice is configured to change its operating channel.

For example, the apparatus may be an OBSS AP and the first device may bethe hopping AP. Moreover, the information may include an indication thatthe hopping AP channel hops on a short-term basis (e.g., at a higherrate than the apparatus) if a minimum allowed time interval between hopsis below a threshold. The OBSS AP may receive the information from thehopping AP, an anchor AP corresponding to the hopping AP, or a STAassociated with the OBSS AP. Accordingly, at block 510, the OBSS AP mayprevent association between the station and the hopping AP based on theindication by excluding the hopping AP in the neighbor report. Also forexample, the first device may be the hopping AP. The hopping AP may beconfigured to change its operating channel according to a first minimumtime interval (e.g., a minimum time interval between hops). At block510, the apparatus may exclude the hopping AP from the availableneighbor list if the first minimum time interval is less than athreshold (e.g., a predetermined threshold).

At block 515, the apparatus may include a third device (e.g., anchorAP), associated with the first device and having channel informationcorresponding to the first device, in the available device list thatallows a second device (e.g., STA) to connect with the first deviceafter association with the third device.

According to one aspect, the third device (e.g., anchor AP) may beconfigured to change its operating channel according to a second minimumtime interval (e.g., a minimum time interval between hops). At block515, the apparatus may include the third device in the available devicelist if the second minimum time interval is greater than a threshold(e.g., a predetermined threshold).

According to another aspect, the first device (e.g., hopping AP) may beconfigured to change its operating channel according to a first minimumtime interval, and the third device (e.g., anchor AP) may be configuredto change its operating channel according to a second minimum timeinterval.

With reference back to block 510, the apparatus may exclude the firstdevice from the available device list if the first minimum time interval(corresponding to the first device) is less than the second minimum timeinterval (corresponding to the third device).

At block 520, the apparatus outputs the neighbor report for transmissionto a second device. For example, the OBSS AP may transmit the neighborreport to the station. Because the hopping AP does not appear in thereport as an AP available for association, the station is prevented fromsearching for the hopping AP when performing a scan based on thereceived neighbor report.

FIG. 6 is a flowchart of an example method 600 of wirelesscommunication. The method 600 may be performed using a first apparatus(e.g., the wireless device 202 of FIG. 2, STA 106, or STA 406). Forexample, the functions described in connection with FIG. 6 may beprogrammed as particular computer-readable instructions in memory 206.The wireless device 202 may then achieve the described functions whenthe processor 204 executes the stored instructions programmed into thememory 206. Although the method 600 is described below with respect tothe elements of wireless device 202 of FIG. 2, other components may beused to implement one or more of the steps described herein.

The apparatus may be a STA (e.g., STA 106 or STA 406). At block 605, theapparatus attempts communication with a first device (e.g., hopping AP)via a first channel. Herein, an attempt at communication may include theapparatus sending out data or preparing data to be sent out, and doesnot require the first device to successfully receive the data from theapparatus.

At block 610, the apparatus determines that the communication attemptwith the first device via the first channel is unsuccessful. Forexample, the apparatus makes such determination if the apparatus doesnot detect a device beacon for a number of beacon cycles, or if theapparatus does not detect a frame from the first device for a period oftime.

At block 615, the apparatus connects with the second device associatedwith the first device in response to the determination thatcommunication with the first device was unsuccessful on the firstchannel. At block 620, the apparatus receives channel informationassociated with the first device from the second device. The channelinformation indicates the second channel used by the first device.

At block 625, the apparatus attempts communication with the first devicevia the second channel based on the channel information received fromthe second device. The channel information may include a time for usingthe second channel to communicate with the first device.

In an aspect, the first device is a hopping access point and the seconddevice is an anchor access point. Accordingly, the apparatus may befurther configured to receive an indication that the anchor access pointis associated with the hopping access point. Moreover, the apparatus maybe configured to connect with the anchor access point by selecting theanchor access point from one or more available access points based onthe indication that the anchor access point is associated with thehopping access point.

In a further aspect, the apparatus may be configured to connect with thesecond device by selecting the second device that is co-located within asame physical housing component as the first device.

In an aspect, a coverage area of the second device may be larger than acoverage area of the first device.

In an aspect, the apparatus is an access terminal, the first device is ahopping access point, and the second device is an anchor access pointthat supports the hopping access point.

In an aspect, the apparatus may be configured to receive a scanningschedule from the first device, the scanning schedule comprising one ormore candidate channels and a scan period corresponding to theapparatus, measure a load on each of the one or more candidate channelsduring the scan period, and report the measured load on each of the oneor more candidate channels to the first device.

In a further aspect, at least one non-scanning apparatus may bescheduled to be served by the first device during the scan period.

In yet another aspect, the apparatus may be configured to connect withthe second device by receiving mapping information including a mappingbetween the first device and the second device. The mapping indicatesthat the second device is designated for indicating the second channelused by the first device if communication with the first device isunsuccessful on the first channel. The apparatus may further beconfigured to communicate with the second device in response to adetermination that a transmission has not been received from the firstdevice for a period of time that is greater than a predetermined timethreshold.

In an aspect, the apparatus (e.g., STA) may receive the channelinformation from the first device (hopping AP) via a hopping APassociation/probe response. In another aspect, the STA may receive thechannel information from the second device (anchor AP) via an anchor APbeacon. In some implementations, the hopping AP and the anchor AP haveoverlapping coverage areas and the hopping AP channel hops at a higherrate than the anchor AP.

The STA may receive the channel information associated with the hoppingAP according to the following operation. First, the STA receives mappinginformation indicating a mapping between the hopping AP and an anchorAP. The STA may communicate with the anchor AP when a transmission isnot received from the hopping for a period of time. The STA may thenreceive a neighbor report from the anchor AP, wherein the neighborreport indicates the second channel associated with the hopping AP.Accordingly, the STA may attempt communication with the hopping AP viathe second channel when the indicated second channel is not the same asthe first channel. Alternatively, the STA may refrain from communicatingwith the hopping AP via the second channel when the indicated secondchannel is the same as the first channel.

The STA may receive the channel information by receiving a neighborreport from the hopping AP. The neighbor report may indicate the anchorAP corresponding to the hopping AP. The neighbor report may furtherinclude identification of a channel of the anchor AP. Accordingly, whencommunication with the hopping AP via the first channel fails, the STAmay refrain from communicating with the hopping AP, and determine tocommunicate with the anchor AP via the channel of the anchor AP.

FIG. 7 is a flowchart of an example method 700 of wirelesscommunication. The method 700 may be performed using an apparatus (e.g.,the wireless device 202 of FIG. 2). For example, the functions describedin connection with FIG. 7 may be programmed as particularcomputer-readable instructions in memory 206. The wireless device 202may then achieve the described functions when the processor 204 executesthe stored instructions programmed into the memory 206. Although themethod 700 is described below with respect to the elements of wirelessdevice 202 of FIG. 2, other components may be used to implement one ormore of the steps described herein.

The apparatus may be configured to communicate with a station (e.g., STA106 or STA 406) regarding association between the station and a firstdevice. At block 705, the apparatus detects a capability of the stationto associate with the first device. The first device has an overlappingcoverage area with a second device, wherein the first device channelhops at a higher rate than the second device. At block 710, theapparatus determines whether to facilitate association between thestation and the first device based on the capability of the station.

The apparatus may be the first device, which may be a hopping AP capableof channel hopping on a short-term basis. Accordingly, the hopping APmay determine to associate with the station when the station is capableof associating with the hopping AP. In an example, the station is“capable” of associating with the hopping AP if the station is able torecognize an anchor AP associated with the hopping AP and retrieve thehopping AP's hopping schedule from the anchor AP when the station losestrack of the hopping AP's movement.

The hopping AP may associate with stations that are not capable ofchannel hopping at the higher rate. Accordingly, the hopping AP maydisable channel hopping at the higher rate when the hopping AP servessuch stations.

Alternatively, the apparatus may be the second device, which may be ananchor AP or OBSS AP. Moreover, the first device may be a hopping AP.Accordingly, the anchor AP or OBSS AP may exclude the hopping AP in aneighbor report sent to the station when the station is not capable ofassociating with the hopping AP. Alternatively, the anchor AP or OBSS APmay detect that the hopping AP has disabled channel hopping at thehigher rate. Accordingly, the anchor AP or OBSS AP may identify thehopping AP as a device that does not channel hop at the higher rate inthe neighbor report sent to the station.

The apparatus may be the first device, which may be a hopping APoperating on a 5-GHz bandwidth. Accordingly, the hopping AP mayassociate with the station when the station is capable of associatingwith the hopping AP.

Alternatively, the apparatus may be the second device, which may be aregular AP operating on a 5-GHz bandwidth, and the first device is thehopping AP. Accordingly, the regular AP may associate with the stationwhen the station is not capable of associating with the hopping AP.

FIG. 8 is a flowchart of an example method 800 of wirelesscommunication. The method 800 may be performed using a first apparatus(e.g., the wireless device 202 of FIG. 2). For example, the functionsdescribed in connection with FIG. 8 may be programmed as particularcomputer-readable instructions in memory 206. The wireless device 202may then achieve the described functions when the processor 204 executesthe stored instructions programmed into the memory 206. Although themethod 800 is described below with respect to the elements of wirelessdevice 202 of FIG. 2, other components may be used to implement one ormore of the steps described herein.

At block 805, the first apparatus receives a channel hopping schedule ofa second apparatus. At block 810, the first apparatus detects a timewhen the second apparatus will channel hop to a channel based on thechannel hopping schedule. At block 815, the first apparatus performs anoperation related to channel hopping based on the detected time.

The first apparatus may be a hopping AP and the second apparatus may beanother hopping AP. The hopping AP and the other hopping AP are capableof channel hopping on a short-term basis. Moreover, the channel hoppingschedule is received from a neighbor anchor AP corresponding to theother hopping AP. The neighbor anchor AP and the other hopping AP haveoverlapping coverage areas and the other hopping AP channel hops at ahigher rate than the neighbor anchor AP. Furthermore, the apparatus maydelay channel hopping to the channel for a period after the detectedtime.

Alternatively, the first apparatus may be an anchor AP and the secondapparatus may be a neighbor hopping AP. The neighbor hopping AP channelhops at a higher rate than the anchor AP. Accordingly, the anchor AP mayinform a hopping AP corresponding to the anchor AP not to channel hop tothe channel before the end of a period after the detected time. Theanchor AP and the hopping AP have overlapping coverage areas and thehopping AP channel hops at a higher rate than the anchor AP.

FIG. 9 is a flowchart of an example method 900 of wirelesscommunication. The method 900 may be performed using an apparatus (e.g.,the wireless device 202 of FIG. 2). For example, the functions describedin connection with FIG. 9 may be programmed as particularcomputer-readable instructions in memory 206. The wireless device 202may then achieve the described functions when the processor 204 executesthe stored instructions programmed into the memory 206. Although themethod 900 is described below with respect to the elements of wirelessdevice 202 of FIG. 2, other components may be used to implement one ormore of the steps described herein.

The apparatus may be a hopping-capable AP capable of channel hopping ona short-term basis. At block 905, the hopping-capable AP detects whetherone or more other apparatuses (e.g., one or more APs) are capable ofchannel hopping. At block 910, the hopping-capable AP disables channelhopping when at least one of the one or more other apparatuses isdetected to be capable of channel hopping. At block 915, thehopping-capable AP enables channel hopping when none of the one or moreother apparatuses is detected to be capable of channel hopping.

The hopping-capable AP may enable channel hopping for a maximum durationand disables channel hopping for a minimum duration. The hopping-capableAP may enable channel hopping by selecting a time slot for enabling thechannel hopping and enables the channel hopping during the selected timeslot when none of the one or more other apparatuses is detected to becapable of channel hopping during the selected time slot.

FIG. 10 is a flowchart of an example method 1000 of wirelesscommunication. The method 1000 may be performed using an apparatus(e.g., the wireless device 202 of FIG. 2, or anchor AP 420). Forexample, the functions described in connection with FIG. 10 may beprogrammed as particular computer-readable instructions in memory 206.The wireless device 202 may then achieve the described functions whenthe processor 204 executes the stored instructions programmed into thememory 206. Although the method 1000 is described below with respect tothe elements of wireless device 202 of FIG. 2, other components may beused to implement one or more of the steps described herein.

The apparatus may be an AP (e.g., anchor AP). At block 1015, theapparatus receives a request from a first device (e.g., a STA). Therequest requests channel information regarding a second device (e.g., ahopping AP) associated with the apparatus. By way of example, thecommunication may have been sent by the first device in response to adetermination that a communication with the second device wasunsuccessful.

At block 1020, the apparatus transmits the channel information regardingthe second device to the first device to indicate a channel used by thesecond device and to facilitate an attempt by the first device tocommunicate with the second device via the indicated channel. Accordingto a further aspect, the channel information includes a time for usingthe indicated channel to communicate with the second device.

According to a further aspect, at block 1005, the apparatus transmits anindication that the apparatus (e.g., anchor AP) is associated with thesecond device.

According to a further aspect, at block 1010, the apparatus transmits anindication that identifies the second device as a hopping access point.

According to a further aspect, the apparatus may be co-located within asame physical housing component as the second device. According to afurther aspect, the apparatus may have a coverage area that is largerthan a coverage area of the second device. According to a furtheraspect, the apparatus may receive the request from the first device inresponse to a failed attempt by the first device to connect with thesecond device on a different channel.

FIG. 11 is a flowchart of an example method 1100 of wirelesscommunication. The method 1100 may be performed using an apparatus(e.g., the wireless device 202 of FIG. 2, AP 104, or hopping AP 404).For example, the functions described in connection with FIG. 11 may beprogrammed as particular computer-readable instructions in memory 206.The wireless device 202 may then achieve the described functions whenthe processor 204 executes the stored instructions programmed into thememory 206. Although the method 1100 is described below with respect tothe elements of wireless device 202 of FIG. 2, other components may beused to implement one or more of the steps described herein.

The apparatus may be an AP. For example, the apparatus may be a hoppingAP. For example, the apparatus may be an anchor AP that supports achannel hopping operation of a hopping AP. At block 1105, the apparatustransmits a scanning schedule to one or more devices (e.g., STA 406).The scanning schedule includes one or more candidate channels and a scanperiod corresponding to at least a first device of the one or moredevices. At block 1120, the apparatus receives a report from the firstdevice in response to the scanning schedule. The report indicates a loadon at least one of the one or more candidate channels during the scanperiod.

According to a further aspect, at block 1110, the apparatus may scheduleat least a second device of the one or more devices for datatransmission service between the second device and the apparatus duringthe scan period associated with a load scanning operation by the firstdevice. For example, the apparatus may schedule the second device byarranging for the second device to be served during the scan period, andtransmitting corresponding signaling to the second device. According toyet a further aspect, at block 1115, the apparatus may at least transmitdata to or receive data from the second device during the scan period.

According to a further aspect, with reference back to block 1105, thescanning schedule may further include a second scan period thatcorresponds to at least a second device of the one or more devices.According to yet a further aspect, at block 1130, the apparatus receivesa report from the second device in response to the scanning schedule.The report indicates a load on at least one of the one or more candidatechannels during the second scan period.

According to yet a further aspect, similar to the scheduling at block1110, the apparatus may schedule the first device for data transmissionservice between the first device and the apparatus during the secondscan period associated with a load scanning operation by the seconddevice. According to yet a further aspect, at block 1125, the apparatusmay at least transmit data to or receive data from the first deviceduring the second scan period.

FIG. 12 is a flowchart of an example method 1200 of wirelesscommunication. The method 1200 may be performed using an apparatus(e.g., the wireless device 202 of FIG. 2, STA 106, STA 406). Forexample, the functions described in connection with FIG. 12 may beprogrammed as particular computer-readable instructions in memory 206.The wireless device 202 may then achieve the described functions whenthe processor 204 executes the stored instructions programmed into thememory 206. Although the method 1200 is described below with respect tothe elements of wireless device 202 of FIG. 2, other components may beused to implement one or more of the steps described herein.

The apparatus may be a STA (e.g., STA 106, STA 406). At block 1205, theapparatus receives a scanning schedule from a device (e.g., AP 104,hopping AP 404, anchor AP). The device may be an anchor AP that supportsa channel hopping operation of a hopping AP. The scanning scheduleincludes one or more candidate channels and a scan period correspondingto the apparatus. At block 1210, the apparatus measures a load on atleast one of the one or more candidate channels during the scan periodin response to receipt of the scanning schedule. At block 1215, theapparatus reports the measured load on at least one of the one or morecandidate channels to the device.

According to a further aspect, the scanning schedule may include asecond scan period corresponding to another apparatus. The apparatus maybe scheduled for data transmission service between the apparatus and thedevice during the second scan period associated with a load scanningoperation by a second apparatus. According to yet a further aspect, atblock 1220, the apparatus may at least transmit data to or receive datafrom the device during the second scan period.

The receiver 212, the processor 204 and/or the transmitter 210 may beconfigured to perform one or more functions discussed above with respectto blocks 375, 380, 385, and 390 of FIG. 3C, blocks 505, 510, 515, and520 of FIG. 5, blocks 605, 610, 615, 620, and 625 of FIG. 6, blocks 705and 710 of FIG. 7, blocks 805, 810, and 815 of FIG. 8, blocks 905, 910,and 915 of FIG. 9, blocks 1005, 1010, 1015, and 1020 of FIG. 10, blocks1105, 1110, 1115, 1120, 1125, and 1130 of FIG. 11, and blocks 1205,1210, 1215 and 1220 of FIG. 12.

The various operations of methods described above may be performed byany suitable means capable of performing the operations, such as varioushardware and/or software component(s), circuits, and/or module(s).Generally, any operations illustrated in the figures may be performed bycorresponding functional means capable of performing the operations.

Moreover, means for determining a first load on an operating channel maycomprise the receiver 212 and/or the processor 204 executing one or morealgorithms. Means for determining a second load on the operating channelcaused by at least one node of a basic service set (BSS) associated witha device may comprise the receiver 212 and/or the processor 204executing one or more algorithms. Means for facilitating the at leastone node to initiate scanning of one or more candidate operatingchannels when the first load is greater than a first predeterminedthreshold and the second load is less than a second predeterminedthreshold may comprise the receiver 212, the processor 204, and/or thetransmitter 210 executing one or more algorithms. Means for selectingone of the one or more candidate operating channels as a new operatingchannel based on a scanning report from the at least one node maycomprise the receiver 212, the processor 204 and/or the transmitter 210executing one or more algorithms.

In some implementations, means for receiving information related to afirst device may comprise the receiver 212 and/or the processor 204executing one or more algorithms. Means for excluding the first devicefrom an available device list in a neighbor in response to receiving theindication that the first device is configured to change its operatingchannel may comprise the processor 204 executing one or more algorithms.Means for including a third device, associated with the first device andhaving channel information corresponding to the first device, in theavailable device list that allows a second device to connect with thefirst device after association with the third device may comprise theprocessor 204 executing one or more algorithms. Means for outputting theneighbor report for transmission to the second device may comprise theprocessor 204 and/or the transmitter 210 executing one or morealgorithms.

In some implementations, means for attempting communication with a firstdevice via a first channel may comprise the receiver 212, the processor204, and/or the transmitter 210 executing one or more algorithms. Meansfor connecting with a second device associated with the first device inresponse to a determination that communication with the first device wasunsuccessful on the first channel may comprise the receiver 212, theprocessor 204, and/or the transmitter 210 executing one or morealgorithms. Means for receiving channel information associated with thefirst device from the second device, wherein the channel informationindicates a second channel used by the first device may comprise thereceiver 212 and/or the processor 204 executing one more algorithms.Means for attempting communication with the second device via the secondchannel based on the channel information may comprise the receiver 212,the processor 204, and/or the transmitter 210 executing one or morealgorithms.

In some implementations, means for receiving an indication that theanchor access point is associated with the hopping access point, meansfor connecting with the anchor access point by selecting the anchoraccess point from one or more available access points based on theindication that the anchor access point is associated with the hoppingaccess point, means for receiving a scanning schedule from the firstdevice, the scanning schedule comprising one or more candidate channelsand a scan period corresponding to the apparatus, means for measuring aload on each of the one or more candidate channels during the scanperiod, means for reporting the measured load on each of the one or morecandidate channels to the first device, means for receiving mappinginformation including a mapping between the first device and the seconddevice, wherein the mapping indicates that the second device isdesignated for indicating the second channel used by the first device ifcommunication with the first device is unsuccessful on the firstchannel, and means for communicating with the second device in responseto a determination that a transmission has not been received from thefirst device for a period of time that is greater than a predeterminedtime threshold may comprise the receiver 212, the processor 204, and/orthe transmitter 210 executing one or more algorithms.

In some implementations, means for determining that the communicationwith the device via the first primary channel has failed if a devicebeacon is not detected for a number of beacon cycles or if a frame fromthe device is not detected for a period of time may comprise thereceiver 212 and/or the processor 204 executing one or more algorithms.Means for refraining from communicating with the device via the secondprimary channel if the second primary channel is the same as the firstprimary channel may comprise the receiver 212, the processor 204, and/orthe transmitter 210 executing one or more algorithms. Means forreceiving channel changing scheduling information may comprise thereceiver 212 and/or the processor 204 executing one or more algorithms.

In some implementations, means for detecting a capability of a stationto associate with a first device, wherein the first device has anoverlapping coverage area with a second device and the first devicechannel hops at a higher rate than the second device may comprise thereceiver 212 and/or the processor 204 executing one or more algorithms.Means for determining whether to facilitate association between thestation and the first device based on the capability of the station maycomprise the transmitter 210 and/or the processor 204 executing one ormore algorithms.

In some implementations, means for receiving a channel hopping scheduleof another apparatus may comprise the receiver 212 executing one morealgorithms. Means for detecting a time when the other apparatus willchannel hop to a channel based on the channel hopping schedule maycomprise the receiver 212 and/or the processor 204 executing one or morealgorithms. Means for performing an operation related to channel hoppingbased on the detected time may comprise the transmitter 210 and/or theprocessor 204 executing one or more algorithms.

In some implementations, means for detecting whether one or more otherdevices is capable of channel hopping may comprise the receiver 212and/or the processor 204 executing one or more algorithms. Means fordisabling channel hopping when at least one of the one or more otherdevices is detected to be capable of channel hopping may comprise theprocessor 204 executing one or more algorithms. Means for enablingchannel hopping when none of the one or more other apparatuses isdetected to be capable of channel hopping may comprise the processor 204executing one or more algorithms.

In some implementations, means for receiving a request from a firstdevice may include the receiver 212 and/or the processor 204 executingone or more algorithms. Means for transmitting channel informationregarding a second device to the first device may include thetransmitter 210 and/or the processor 204 executing one or morealgorithms. In further implementations, means for transmitting anindication that the anchor access point is associated with the seconddevice may include the transmitter 210 and/or the processor 204executing one or more algorithms. In further implementations, means fortransmitting an indication that identifies the second device as ahopping AP may include the transmitter 210 and/or the processor 204executing one or more algorithms.

In some implementations, means for transmitting a scanning schedule toone or more devices may include the transmitter 210 and/or the processor204 executing one or more algorithms. Means for receiving a report froma first device in response to the scanning schedule may include thereceiver 212 and/or the processor 204 executing one or more algorithms.In further implementations, means for scheduling at least a seconddevice for data transmission service between the second device and anapparatus during the scan period may include the transmitter 210, thereceiver 212 and/or the processor 204 executing one or more algorithms.In further implementation, means for transmitting data to the seconddevice during the scan period may include the transmitter 210 and/or theprocessor 204 executing one or more algorithms, and/or means forreceiving data from the second device during the scan period may includethe receiver 212 and/or the processor 204 executing one or morealgorithms. In further implementations, means for receiving a reportfrom the second device in response to the scanning schedule may includethe receiver 212 and/or the processor 204 executing one or morealgorithms. In further implementation, means for transmitting data tothe first device during the second scan period may include thetransmitter 210 and/or the processor 204 executing one or morealgorithms, and/or means for receiving data from the first device duringthe second scan period may include the receiver 212 and/or the processor204 executing one or more algorithms.

In some implementations, means for receiving a scanning schedule from adevice may include the receiver 212 and/or the processor 204 executingone or more algorithms. Means for measuring a load on at least one ofthe one or more candidate channels during the scan period in response toreceipt of the scanning schedule may include the receiver 212 and/or theprocessor 204 executing one or more algorithms. Means for reporting themeasured load on at least one of the one or more candidate channels tothe device may include the transmitter 210 and/or the processor 204executing one or more algorithms. In further implementations, means fortransmitting data to the device during a second scan period may includethe transmitter 210 and/or the processor 204 executing one or morealgorithms, and/or means for receiving data from the device during thesecond scan period may include the receiver 212 and/or the processor 204executing one or more algorithms.

As used herein, the term “associate,” or “association,” or any variantthereof should be given the broadest meaning possible within the contextof the present disclosure. By way of example, when a first apparatusassociates with a second apparatus, it should be understood that the twoapparatus may be directly associated or intermediate apparatuses may bepresent. For purposes of brevity, the process for establishing anassociation between two apparatuses will be described using a handshakeprotocol that requires an “association request” by one of the apparatusfollowed by an “association response” by the other apparatus. It will beunderstood by those skilled in the art the handshake protocol mayrequire other signaling, such as by way of example, signaling to provideauthentication.

Any reference to an element herein using a designation such as “first,”“second,” and so forth does not generally limit the quantity or order ofthose elements. Rather, these designations are used herein as aconvenient method of distinguishing between two or more elements orinstances of an element. Thus, a reference to first and second elementsdoes not mean that only two elements can be employed, or that the firstelement must precede the second element. In addition, a phrase referringto “at least one of” a list of items refers to any combination of thoseitems, including single members. As an example, “at least one of: A, B,or C” is intended to cover: A or B or C, or A and B, or A and C, or Band C, or A, B and C, or 2A, or 2B, or 2C, and so on.

The various illustrative logical blocks, modules and circuits describedin connection with the present disclosure may be implemented orperformed with a general purpose processor, a digital signal processor(DSP), an application specific integrated circuit (ASIC), a fieldprogrammable gate array signal (FPGA) or other programmable logic device(PLD), discrete gate or transistor logic, discrete hardware componentsor any combination thereof designed to perform the functions describedherein. A general purpose processor may be a microprocessor, but in thealternative, the processor may be any commercially available processor,controller, microcontroller or state machine. A processor may also beimplemented as a combination of computing devices, e.g., a combinationof a DSP and a microprocessor, a plurality of microprocessors, one ormore microprocessors in conjunction with a DSP core, or any other suchconfiguration.

The functions described herein may be implemented in hardware, software,firmware, or any combination thereof. If implemented in software, thefunctions may be stored on or transmitted over as one or moreinstructions or code on a computer-readable medium. Computer-readablemedia includes both computer storage media and communication mediaincluding any medium that facilitates transfer of a computer programfrom one place to another. A storage media may be any available mediathat can be accessed by a computer. By way of example, and notlimitation, such computer-readable media can comprise RAM, ROM, EEPROM,CD-ROM or other optical disk storage, magnetic disk storage or othermagnetic storage devices, or any other medium that can be used to carryor store desired program code in the form of instructions or datastructures and that can be accessed by a computer. Also, any connectionmay be termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), then the coaxial cable, fiber optic cable, twisted pair, or DSLare included in the definition of medium. The software may also betransmitted from the website, server, or other remote source usingwireless technologies such as infrared, radio, and microwave. Disk anddisc, as used herein, includes compact disc (CD), laser disc, opticaldisc, digital versatile disc (DVD), floppy disk and blu-ray disc wheredisks usually reproduce data magnetically, while discs reproduce dataoptically with lasers. Thus, computer readable medium may comprisenon-transitory computer readable medium (e.g., tangible media).Combinations of the above should also be included within the scope ofcomputer-readable media.

The methods disclosed herein comprise one or more steps or actions forachieving the described method. The method steps and/or actions may beinterchanged with one another without departing from the scope of theclaims. In other words, unless a specific order of steps or actions isspecified, the order and/or use of specific steps and/or actions may bemodified without departing from the scope of the claims.

Certain implementations may comprise a computer program product forperforming the operations presented herein. For example, such a computerprogram product may comprise a computer readable medium havinginstructions stored (and/or encoded) thereon, the instructions beingexecutable by one or more processors to perform the operations describedherein. For certain implementations, the computer program product mayinclude packaging material.

It should be appreciated that modules and/or other appropriate means forperforming the methods and techniques described herein can be downloadedand/or otherwise obtained by a user terminal and/or base station asapplicable. For example, such a device can be coupled to a server tofacilitate the transfer of means for performing the methods describedherein. Alternatively, various methods described herein can be providedvia storage media, such that a user terminal and/or base station canobtain the various methods upon coupling or providing a storage mediumto the device. Moreover, any other suitable technique for providing themethods and techniques described herein to a device can be utilized.

It is to be understood that the claims are not limited to the preciseconfiguration and components illustrated above. Various modifications,changes and variations may be made in the arrangement, operation anddetails of the methods and apparatus described above without departingfrom the scope of the claims.

While the foregoing is directed to aspects of the present disclosure,other and further aspects of the disclosure may be devised withoutdeparting from the basic scope thereof, and the scope thereof isdetermined by the claims that follow.

What is claimed is:
 1. An apparatus for wireless communication,comprising: a processing system configured to: attempt communicationwith a first device via a first channel; connect with a second deviceassociated with the first device in response to a determination thatcommunication with the first device was unsuccessful on the firstchannel; and receive channel information associated with the firstdevice from the second device, wherein the channel information indicatesa second channel used by the first device.
 2. The apparatus of claim 1,wherein the processing system is further configured to: attemptcommunication with the first device via the second channel based on thechannel information received from the second device.
 3. The apparatus ofclaim 1, wherein the first device is a hopping access point and thesecond device is an anchor access point; wherein the processing systemis further configured to receive an indication that the anchor accesspoint is associated with the hopping access point; and wherein theprocessing system is configured to connect with the anchor access pointby being configured to select the anchor access point from one or moreavailable access points based on the indication that the anchor accesspoint is associated with the hopping access point.
 4. The apparatus ofclaim 1, wherein the processing system is configured to connect with thesecond device by being configured to select the second device that isco-located within a same physical housing component as the first device.5. The apparatus of claim 1, wherein the apparatus is an accessterminal, the first device is a hopping access point, and the seconddevice is an anchor access point that supports the hopping access point.6. The apparatus of claim 1, wherein the processing system is furtherconfigured to: receive a scanning schedule from the first device, thescanning schedule comprising one or more candidate channels and a scanperiod corresponding to the apparatus; measure a load on each of the oneor more candidate channels during the scan period; and report themeasured load on each of the one or more candidate channels to the firstdevice.
 7. The apparatus of claim 6, wherein at least one non-scanningapparatus is scheduled to be served by the first device during the scanperiod.
 8. The apparatus of claim 1, wherein the processing system isconfigured to connect with the second device by being configured to:receive mapping information including a mapping between the first deviceand the second device, wherein the mapping indicates that the seconddevice is designated for indicating the second channel used by the firstdevice if communication with the first device is unsuccessful on thefirst channel; and communicate with the second device in response to adetermination that a transmission has not been received from the firstdevice for a period of time that is greater than a predetermined timethreshold.
 9. The apparatus of claim 1, wherein the channel informationcomprises a time for using the second channel to communicate with thefirst device.
 10. An apparatus for wireless communication, comprising: aprocessing system configured to: receive a request from a first device,the request requesting channel information regarding a second deviceassociated with the apparatus; and transmit the channel informationregarding the second device to the first device to indicate a channelused by the second device and to facilitate an attempt by the firstdevice to communicate with the second device via the indicated channel.11. The apparatus of claim 10, wherein the apparatus is an anchor accesspoint and the second device is a hopping access point, and wherein theprocessing system is further configured to transmit an indication thatthe anchor access point is associated with the second device.
 12. Theapparatus of claim 10, wherein the processing system is furtherconfigured to transmit an indication that identifies the second deviceas a hopping access point.
 13. The apparatus of claim 10, wherein theapparatus is co-located within a same physical housing component as thesecond device.
 14. The apparatus of claim 10, wherein the processingsystem is configured to receive the request from the first device inresponse to a failed attempt by the first device to connect with thesecond device on a different channel.
 15. The apparatus of claim 10,wherein the channel information comprises a time for using the indicatedchannel to communicate with the second device.
 16. A method of wirelesscommunication at an apparatus, comprising: attempting communication witha first device via a first channel; connecting with a second deviceassociated with the first device in response to a determination thatcommunication with the first device was unsuccessful on the firstchannel; and receiving channel information associated with the firstdevice from the second device, wherein the channel information indicatesa second channel used by the first device.
 17. The method of claim 16,further comprising: attempting communication with the first device viathe second channel based on the channel information.
 18. The method ofclaim 16, wherein the first device is a hopping access point and thesecond device is an anchor access point, wherein the method furthercomprises: receiving an indication that the anchor access point isassociated with the hopping access point; and connecting with the anchoraccess point by selecting the anchor access point from one or moreavailable access points based on the indication that the anchor accesspoint is associated with the hopping access point.
 19. The method ofclaim 16, wherein the connecting with the second device comprisesconnecting with the second device by selecting the second device that isco-located within a same physical housing component as the first device.20. The method of claim 16, wherein the apparatus is an access terminal,the first device is a hopping access point, and the second device is ananchor access point that supports the hopping access point.
 21. Themethod of claim 16, further comprising: receiving a scanning schedulefrom the first device, the scanning schedule comprising one or morecandidate channels and a scan period corresponding to the apparatus;measuring a load on each of the one or more candidate channels duringthe scan period; and reporting the measured load on each of the one ormore candidate channels to the first device.
 22. The method of claim 21,wherein at least one non-scanning apparatus is scheduled to be served bythe first device during the scan period.
 23. The method of claim 16,wherein the connecting with the second device comprises: receivingmapping information including a mapping between the first device and thesecond device, wherein the mapping indicates that the second device isdesignated for indicating the second channel used by the first device ifcommunication with the first device is unsuccessful on the firstchannel; and communicating with the second device in response to adetermination that a transmission has not been received from the firstdevice for a period of time that is greater than a predetermined timethreshold.
 24. The method of claim 16, wherein the channel informationcomprises a time for using the second channel to communicate with thefirst device.
 25. A method of wireless communication at an apparatus,comprising: receiving a request from a first device, the requestrequesting channel information regarding a second device associated withthe apparatus; and transmitting the channel information regarding thesecond device to the first device to indicate a channel used by thesecond device and to facilitate an attempt by the first device tocommunicate with the second device via the indicated channel.
 26. Anapparatus for wireless communication, comprising: means for attemptingcommunication with a first device via a first channel; means forconnecting with a second device associated with the first device inresponse to a determination that communication with the first device wasunsuccessful on the first channel; and means for receiving channelinformation associated with the first device from the second device,wherein the channel information indicates a second channel used by thefirst device.
 27. An apparatus for wireless communication, comprising:means for receiving a request from a first device, the requestrequesting channel information regarding a second device associated withthe apparatus; and means for transmitting the channel informationregarding the second device to the first device to indicate a channelused by the second device and to facilitate an attempt by the firstdevice to communicate with the second device via the indicated channel.28. A computer-readable medium storing computer executable code forwireless communication at an apparatus, comprising code for: attemptingcommunication with a first device via a first channel; connecting with asecond device associated with the first device in response to adetermination that communication with the first device was unsuccessfulon the first channel; and receiving channel information associated withthe first device from the second device, wherein the channel informationindicates a second channel used by the first device.
 29. Acomputer-readable medium storing computer executable code for wirelesscommunication at an apparatus, comprising code for: receiving a requestfrom a first device, the request requesting channel informationregarding a second device associated with the apparatus; andtransmitting the channel information regarding the second device to thefirst device to indicate a channel used by the second device and tofacilitate an attempt by the first device to communicate with the seconddevice via the indicated channel.